Fluid pressure control apparatus



May 7, 1935. H. c. wAssoN FLUID PRESSURE CONTROL APPARATUS Filed May 19,1931 A TTORNEY.

/NVEN'To/z. Har/y C. Wasson Patented May 7, 1935 UNITED STATES PATENTOFFICE FLUID PRESSURE CONTROL APPARATUS Harry C. Wasson, Franklin, Pa.,assigner to Chicago Pneumatic Tool Company, New York, N. Y., acorporation of New Jersey Application May 19, 1931, Serial No. 538,447

1 Claim. (Cl. 137-157) This invention relates to fluid pressure controlFig. 3 a sectional view substantially on the line apparatus and moreparticularly to flexible ele- 3--3 of Fig. 2. ments in direct Contactwith the fluid pressure Fig. 1 illustrates diaphragm 4 of the presentmedium. invention embodied in an unloading unit A for 5 One object ofthe invention is to provide an use with a valve assembly Bconventionally 5 improved form of fluid tight partition or diamountedwithin the Walls of a compressor C. phragm for use between a fluid underpressure Body a of the unloading unit serves as a cover and a movableobject to which force is to be plate for the opening in the outer wallof comapplied to produce movement. Other objects pressor C and supportsa movable member a' will be apparent from the detailed description inline with the axis of valve assembly B to acl0 which follows, tuatevalve lifter b to hold'the valves of the unit Exhaustive tests of allthe different diaphragm in open position when the compressor is to beunmaterials show that no one material gives satisloaded. Diaghragm 4 issecurely clamped befactory service over an extended period when tweenbody a and cap plate a2 as the cap screws L, subjected to such frequentoperation as may dea3 extending through openings 4a inthe dial5 velopunder certain conditions as in the unphragm and extends across the topof member loading valve of a compressor or pump, whether a'. Pressurefluid is admitted within cap memof the stationary or portable type. Aleather ber a2 over diaphragm I through an opening a4 diaphragm soonloses its flexibility becoming stiir and the force exerted by thepressure fluid is and brittle, so that it leaks fluid after acomparatransmitted by diaphragm 4 t0 member a'. Unit V530 tively smallnumber of operations. A rubber A may have a hand actuated screw plungera5 diaphragm is soon decomposed by the chemical t0 force member a tounlOading position When action of oil or the like in the pressure fluidand Pressure Huid is not available. Inasmuch as the is unable to supportthe applied pressure. No apparatus disclosed in Fig. 1 merelyillustrates artificial brous material is available which posone use ofthe invention, further description 25 sesses the desired qualities offlexibility, strength, thereof is omitted. and fluid tightness. Theimproved diaphragm shown in Fig. 1 is It has been discovered thatcertain materials illustrated on an enlarged Scale in Figs 2 and 3 maybe used in combination, however, to produce and consists of superposedsheets of dlierent maa diaphragm having satisfactory operatingcharterial with the bolt holes 4a therethrough in 30 acteristics and agreatly extended life. Rubber register. By preference the central layer5 is may be used to secure fluid tightness and leather of suitablematerial to insure against leakage or to give strength and to protectthe rubber from seepage of the pressure fluid through the diaheat,friction, and decomposition. By prefphragm. The additional layer orlayers are to erence a layer of rubber or rubber compound is addstrength to the diaphragm and to protect 35 used between layers ofleather to make a comthe fluid tight layer from damage through heat,posite diaphragm. The layer of rubber or rubber friction, or substancesentrained by the pressure compound may be strengthened, as by fibrousfluid which would cause decomposition by chemimaterial therein, and mayconsist of cloth or cal action. The central layer 5 may be comfabricimpregnated with rubber. In making up posed of rubber or a rubbercompound. For add- 40 the laminated or composite diaphragm it is prefedstrength it may contain fibrous material or erable to assemble thelayers in loose engagemay take the form of a cloth or fabric sheetimment and not to cement or otherwise secure them pregnated with rubberor rubber compound. The to one another since they have differentcoeenclosing sheets 6 and 'l may be of leather or cients of expansionand undue strains result from similar fibrous material having sumcienttough- 45 such a practice. ness to resist wear, sufficient absorption totake In order to illustrate the invention one concrete up oil entrainedwith the pressure fluid and sufembodiment thereof is shown in theaccompanycient flexibility to permit proper operation of ing drawing, inwhich: the composite diaphragm. The sheets forming Fig. 1 illustrates adiaphragm in use in the unthe diaphragm are loosely assembled and notse- 50 loading valve assembly of a compressor, the valve cured to oneanother so that the different coand portions of the compressor wallbeing indieicients of expansion will not result in undesircated inbroken outline; able strains on individual layers or sheets.

Fig. 2 is a plan view on an enlarged scale of the The life of the rubberis prolonged by the action diaphragm; and of the retaining layers ofleather. When, in

course of time, the rubber begins to disintegrate under the action ofthe oil, it forms a gummy substance which plugs thepores in the adjacentleather thus still maintaining uid tightness.

While the invention has been herein shown and described in what is nowconsidered to be a preferred form, it is to be understood that theinvention is not limited to the specic details thereof but covers al1changes, modifications, and adaptations within the scope of the appendedclaim.

I claim as my invention:

A fluid actuated device comprising an enclosure, a substantially fiatdiaphragm dividing said enclosure into two chambers, means for admittingpressure uid to one of said chambers, and a plunger actuated by saiddiaphragm, said diaphragm comprising an inner layer of rubberand outersheets or layers of leather, said layers being in contact with eachother and secured to each other only at the peripheral edges thereof,the central portion of the diaphragm being imperiorate and in looseengagement with a stop member in the fluid chamber and a plunger in theother chamber, the stop members being movable manually with respect tothe enclosure to actuate the diaphragm and plunger.

' HARRY C. WASSON.

CERTIFICATE 0F CORRECTION.

Patent No. 2,000,542. v May 7, 1935.

HARRY C. WASSON.

lt is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1,second column, line 14, for "the" read by; and page 2, second column,line il, the claim, for "members" read member; and that the said LettersPatent should be read with these corrections therein that the same mayconform to the record of the case in the Patent Office.

Signed and sealed this 9th day of July, A. D. i935.

Bryan M. Battey (Seal) Acting Commissioner of Patents.

